Coin shape detection method, coin identification sensor, and coin identification device

ABSTRACT

In a coin configuration detection method and a coin identification sensor that magnetically detect the coin configuration, coin configuration detection is enabled to be accurately performed. Moreover, in a coin identification apparatus, the coin identification accuracy is improved. In a coin configuration detection method (coin identification sensor  1 ) that magnetically detects the configuration of a coin  2  to identify the kind and/or the authenticity of the coin  2 , a magnetic flux change in the vicinity of the surface of the coin  2  is detected by a detection coil  7  in which a coil central line is along the surface of the coin  2  and a coil peripheral surface is locally opposed to the surface of the coin  2  while an AC magnetic field along the surface of the coin  2  is generated in the interior of the coin  2  and/or in the surface space of the coin  2 . Moreover, the coin identification apparatus identifies the coin  2  based on the detection signal of the coin identification sensor  1.

This application claims priority from JP 2002-126589, filed Apr. 26,2002, through PCT/JP03/05130, filed Apr. 22, 2003, and the disclosuresof both applications are incorporated herein by reference thereto.

BACKGROUND OF THE INVENTION

1. Technical Field

The invention relates to a coin configuration detection method and acoin identification sensor that magnetically detects the configurationof a coin to identify the kind and/or the authenticity of the coin. Theinvention further relates to a coin identification apparatus thatidentifies the kind and/or the authenticity of a coin based on theconfiguration detected by the coin identification sensor.

2. Description of Related Art

Various coin identification sensors that detect the surfaceconfiguration of a coin in a non-contact manner have been developed.These kinds of coin identification sensors are broadly divided into onesusing optical means and ones using magnetic means.

As optical coin identification sensors, the following are known: onethat photographs the coin surface by use of an optical image sensor,such as a CCD sensor, and processes the photographic data to therebyidentify the surface configuration; and one that receives reflectedlight from the coin surface by a light receiving device, such as aphotodiode, and identifies the coin surface configuration based on thelight reception level. But optical coin identification sensors are notonly susceptible to dirt on the coin surface but also have a drawbackthat they cannot detect the height and depth of the asperities.

On the other hand, as a magnetic coin identification sensor, one isknown that uses the eddy current effect of a conductor in an AC magneticfield. Eddy current is generated when a conductor, such as a metal, isplaced in an AC magnetic field, within the conductor so as to prevent achange in the magnetic flux passing through the conductor. Because thegeneration condition thereof varies according to the surfaceconfiguration of the conductor, the surface configuration can bedetected by detecting a magnetic flux change due to the eddy current inthe vicinity of the surface of the conductor without being affected bydirt on the conductor surface. As such a coin identification sensor, forexample, one is known in which a plurality of detection coils disposedin a matrix is opposed to the coin surface and the surface configurationis detected (for example, see Japanese Published Unexamined PatentApplication No. 2001-126103 and Japanese Published Unexamined PatentApplication No. 2002-24894).

However, conventional magnetic coin identification sensors are limitedin detection accuracy because they detect, while generating an ACmagnetic field on the coil surface by an exciting coil in which the coilcentral line is vertical to the coin surface in the vicinity of the coinsurface, the magnetic flux change in the vicinity of the coin surface bya detection coil in which the coil central line is vertical to the coinsurface. That is, the detection of the surface configuration is, whenthe surface configuration is expressed by coordinates (X, Z) as shown inFIG. 13(A), to detect ΔZ/ΔX, and to detect this accurately, it isrequired that ΔX be as small as possible; however, because the detectionarea of a conventional coin identification sensor 100 is not less thanfour times the coil diameter D as shown in FIG. 13(B), the resolution inthe X direction is low, so that a fine surface configuration cannot bedetected.

SUMMARY OF THE INVENTION

In view of the above-mentioned circumstances, a coin configurationdetection method of the invention created for the purpose of solvingthese problems is a coin configuration detection method thatmagnetically detects the configuration of a coin to identify the kindand/or the authenticity of the coin, and is characterized in that amagnetic flux change in the vicinity of the surface of the coin isdetected by a detection coil in which the coil central line is along thesurface of the coin and the coil peripheral surface is locally opposedto the surface of the coin while an AC magnetic field in the directionalong the surface of the coin is generated in the interior of the coinand/or in the surface space of the coin.

According to this coin configuration detection method, although an ACmagnetic field along the coin surface is generated to thereby cause amagnetic change due to the surface configuration of the coin to emergeas a magnetic flux change mainly along the coin surface, the magneticflux change is detected not by detection coils disposed vertically tothe coin surface but by the detection coils disposed along the coinsurface, whereby even a minute magnetic flux change whose verticalcomponent hardly changes can be detected. Consequently, even a finesurface configuration of the coin can be detected, so that the coinconfiguration detection accuracy can be dramatically improved. Further,because it is easy to reduce the size of the detection coils in thedirection along the coin surface, the resolution of the coinconfiguration detection can be easily improved by reducing the AX asmuch as possible.

Moreover, in view of the above-mentioned circumstances, a coinidentification sensor of the invention created for the purpose ofsolving these problems is a coin identification sensor that magneticallydetects the configuration of a coin to identify the kind and/or theauthenticity of the coin, and is provided with an exciting portion thatgenerates an AC magnetic field in the direction along the surface of thecoin in the interior of the coin and/or in the surface space of thecoin; and a detection coil that is disposed so that the coil centralline is along the surface of the coin and the coil peripheral surface islocally opposed to the surface of the coin, and detects a magnetic fluxchange in the vicinity of the surface of the coin.

When the coin identification sensor is structured as described above,while an AC magnetic field along the coin surface is generated tothereby cause a magnetic change due to the surface configuration of thecoin to emerge as a magnetic flux change mainly along the coin surface,the magnetic flux change is detected not by detection coils disposedvertically to the coin surface but by the detection coils disposed alongthe coin surface, whereby even a minute magnetic flux change whosevertical component hardly changes can be detected. Consequently, even afine surface configuration of the coin can be detected, so that the coinconfiguration detection accuracy can be dramatically improved. Further,because it is easy to reduce the size of the detection coils in thedirection along the coin surface, the resolution of the coinconfiguration detection can be easily improved by reducing the ΔX asmuch as possible.

Moreover, in the coin identification sensor, the exciting portion is anexciting coil disposed so that the coil inner surface or the coilperipheral surface is along the surface of the coin and generating an ACmagnetic field in the direction along the surface of the coin in theinterior of the coin and/or in the surface space of the coin, and thedetection coil is disposed in an inner portion of the exciting coil orin the vicinity thereof, or in a peripheral portion of the exciting coilor in the vicinity thereof. In this case, not only can the detectionaccuracy be improved by increasing the magnetic field intensity in thevicinity of the detection coil but also the coin identification sensorcan be reduced in size.

Moreover, in the coin identification sensor, the exciting portion has aplurality of coin adjacent portions, and is provided with aferromagnetic core that forms a looped magnetic circuit with theinterior of the coin and/or the surface space of the coin inside and anexciting coil that AC-excites the core and generates an AC magneticfield in the direction along the surface of the coin in the interior ofthe coin and/or in the surface space of the coin. In this case, becausea strong magnetic field can be locally generated on the surface of thecoin, the detection accuracy of the coin identification sensor can beimproved.

Moreover, in the coin identification sensor, the detection coil is adifferential coil capable of detecting a differential voltage, and apair of coils constituting the differential coil line along the surfaceof the coin. In this case, the detection accuracy can be furtherimproved by canceling out intrinsic errors and temperature errors of thecoils.

Moreover, in the coin identification sensor, the detection coil isprovided in a plurality of numbers so as to line along the surface ofthe coin. In this case, by scanning the coin identification sensor orthe coin in a direction perpendicular to the direction in which thedetection coils align, two-dimensional detection data can be obtained,and by two-dimensionally disposing a plurality of detection coils,two-dimensional detection data can be obtained without the coinidentification sensor or the coin being scanned.

Moreover, in view of the above-mentioned circumstances, a coinidentification apparatus of the invention created for the purpose ofsolving these problems is a coin identification apparatus thatidentifies the kind and/or the authenticity of a coin, and theconfiguration of the coin is detected by the above-described coinidentification sensor and the kind and/or the authenticity of the coinis identified based on the detected configuration.

When the coin identification apparatus is structured as described above,because the kind and/or the authenticity of the coin is identified basedon highly accurate configuration detection data by the above-describedcoin identification sensor, the identification accuracy of the coinidentification apparatus can be dramatically improved.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described with reference to the drawings in which:

FIG. 1(A) is a plan view of a coin identification sensor showing a firstembodiment, FIG. 1(B) is a front view, and FIG. 1(C) is a side view;

FIG. 2(A) is a perspective view of a coin identification sensor showingthe first embodiment, and FIG. 2(B) is an internal perspective view;

FIG. 3 is a working explanatory view of the coin identification sensorin the first embodiment;

FIG. 4 is an enlarged view of detection coils;

FIG. 5 is a block diagram of a detection circuit;

FIG. 6(A) is a schematic view of a coin identification sensor showing asecond embodiment, and FIG. 6(B) is a schematic view showing a coinidentification sensor showing a third embodiment;

FIG. 7 is a schematic view of a coin identification sensor showing afourth embodiment;

FIGS. 8(A) to 8(F) are explanatory views showing various forms of coresin the coin identification sensor of the fourth embodiment;

FIGS. 9(A) to 9(C) are explanatory views showing various forms ofexciting coils in the coin identification sensor of the fourthembodiment;

FIGS. 10(A) to 10(C) are explanatory views showing various forms ofdetection coils in the coin identification sensor of the fourthembodiment with FIG. 10(A) a side view, FIG. 10(B) a plan view, and FIG.10(C) a cross sectional side view, severally showing detection coils inthe coin identification sensor of the fourth embodiment;

FIGS. 11(A) to 11 (C) are explanatory views showing various forms ofdetection coils in the coin identification sensor of the fourthembodiment with FIG. 11(A) showing an elevational view and a side view,FIG. 11(B) an elevational view, and FIG. 11(C) a plan view, severallyshowing detection coils in the coin identification sensor of the fourthembodiment;

FIG. 12 is a schematic view of a coin identification sensor according toa fifth embodiment; and

FIG. 13(A) is a view showing the surface configuration as X and Ycoordinates, and FIG. 13(B) is an explanatory view showing theconventional coin identification sensor.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1(A) is a plan view of a coin identification sensor showing a firstexemplary embodiment, FIG. 1(B) is a front view, FIG. 1(C) is a sideview, FIG. 2(A) is a perspective view of the coin identification sensorshowing the first embodiment, and FIG. 2(B) is an internal perspectiveview. The coin identification sensor 1 shown in these figures isdisposed on a coin passage 3 where a coin 2 passes, and magneticallydetects the surface configuration of the coin 2 passing along the coinpassage 3.

The coin identification sensor 1 of the first embodiment is providedwith an exciting coil (exciting portion) 5 that is wound around theperiphery of a coil bobbin 4; an AC exciting circuit portion 6 (FIG. 5)that AC-excites the exciting coil 5; a plurality of detection coils 7disposed on the inner surface of the coil bobbin 4; and a detectioncircuit portion 8 that takes out the detection signals of the detectioncoils 7. The coil bobbin 4 is, for example, a rectangular-tube-formresin mold. On the inner portion thereof, a coin passage 4 a throughwhich the coin 2 can pass is formed, and on the periphery thereof, acoil winding groove 4 b for winding the exciting coil 5 is formed.

The exciting coil 5 is AC-excited at a predetermined frequency by the ACexciting circuit portion 6 to generate an AC magnetic field. The ACmagnetic field is generated in the direction along the surface of thecoin 2 situated in the coin passage 4 a, and causes a magnetic changedue to the coin surface configuration to emerge as a magnetic fluxchange of a parallel component mainly along the coin surface. Thedetection coils 7 are disposed so that the coil central lines are alongthe coin surface and the coil peripheral surfaces are locally opposed tothe coin surface. When the coin 2 is situated in the coin passage 4 a,the detection coils 7 detect a magnetic flux change along the surface ofthe coin 2 in the vicinity of the surface of the coin 2.

That is, as shown in FIG. 3, the coin identification sensor 1 detects,while generating an AC magnetic field along the surface of the coin 2 tothereby cause a magnetic change due to the surface configuration of thecoin 2 to emerge as a magnetic flux change mainly along the surface ofthe coin 2, the magnetic flux change is detected, not by detection coilsdisposed vertically to the surface of the coin 2, rather by thedetection coils 7 disposed along the surface of the coin 2, whereby evena minute magnetic flux change whose vertical component hardly changescan be detected. Consequently, even a fine surface configuration of thecoin 2 can be detected, so that the coin configuration detectionaccuracy can be dramatically improved.

Moreover, in the thus structured coin identification sensor 1, theresolution in the ΔX direction can be determined based on the size ofthe detection coils 7 in the direction of the coil central lines.Further, because the above-mentioned size is easily reduced by usingspiral coils or multilayer coils as the detection coils 7, theresolution of the coin configuration detection can be easily improved byreducing the ΔX as much as possible. Moreover, because the detectioncoils 7 are disposed on the inner surface of the exciting coil 5, whilea strong magnetic field is generated in the vicinity of the detectioncoils 7, the magnetic flux change can be accurately detected by thedetection coils 7. In the figures, reference numeral 9 represents amolded resin in which the detection coils 7 are held in a buriedcondition.

Moreover, in the coin identification sensor 1, a plurality of detectioncoils 7 is disposed at predetermined intervals in the circumferentialdirection on the inner surface of the coil bobbin 4. By this, not onlycan the surface configuration of the coin 2 be detected by the pluralityof detection coils 7 while the exciting coil 5 is also used but also thesurface configuration of the coin 2 can be two-dimensionally scanned bymoving the coin identification sensor 1 and the coin 2 relative to oneanother. Further, according to the first embodiment, because theplurality of detection coils 7 is disposed in opposing positions on theinner surface of the coil bobbin 4, the obverse side surfaceconfiguration and the reverse side surface configuration of the coin 2can be detected at the same time.

FIG. 4 is an enlarged view of the detection coils, and FIG. 5 is a blockdiagram of the detection circuit. As shown in these figures, thedetection coils 7 of the present embodiment are formed by winding (forexample, a width of 1.0 mm) a pair of detection coils L1, L2 disposed ina line along the surface of the coin 2 on a cylindrical core material 10having a diameter of, for example, 0.5 mm. The detection coils L1, L2are connected in series, and a center tap terminal T3 derived betweenthe detection coils L1, L2 is provided as well as terminals T1, T2derived from both ends of the detection coils L1, L2.

As shown in FIG. 5, the detection coils L1, L2 constitute a bridgecircuit 11 together with a pair of resistors R1, R2 (or variableresistors), and the differential voltage of the detection coils L1, L2is outputted from the bridge circuit 11. In the bridge circuit 11, theresistance values of the resistors R1, R2 are initially adjusted so thatthe differential output is a predetermined value when the coin 2 isabsent in the coin passage 4 a. By this, not only can a detection signalin which intrinsic errors and temperature errors of the detection coilsL1, L2 are canceled out be obtained but also the resolution in the ΔXdirection can be improved.

The differential output of the bridge circuit 11 is amplified by adifferential amplifier circuit 12 and is then inputted to a synchronousdetection circuit 13. The synchronous detection circuit 13 receives asynchronization signal from the AC exciting circuit portion 6 through a90° phase shifter 14, and detects the differential output in the cyclethereof to obtain a magnetic flux change signal. The magnetic fluxchange signal passes through an integration circuit 15 and is thenoutputted as a surface configuration detection signal from the coinidentification sensor 1. In this connection, the output signal of thecoin identification sensor 1 is inputted to a higher controller and usedfor the identification of the coin 2 in the controller.

In the apparatus structured as described above, the coin identificationsensor 1 detects, while generating an AC magnetic field along thesurface of the coin 2 to thereby cause a magnetic change due to thesurface configuration of the coin 2 to emerge as a magnetic flux changeof a parallel component mainly along the surface of the coin 2, themagnetic flux change, not by detection coils disposed vertically to thesurface of the coin 2, rather by the detection coils 7 disposed alongthe surface of the coin 2, whereby even a minute magnetic flux changewhose vertical component hardly changes can be detected. By this, even afine surface configuration of the coin 2 can be detected, so that thecoin configuration detection accuracy can be dramatically improved.Further, because it is easy to reduce the size of the detection coils 7in the direction along the coin surface, the resolution of the coinconfiguration detection can be easily improved by reducing the AX asmuch as possible.

Moreover, because the exciting coil 5 is disposed so that the coil innersurface is along the surface of the coin 2 and generates an AC magneticfield in the direction along the surface of the coin 2 in the interiorand the surface space of the coin 2 and the detection coils 7 aredisposed in the inner surface portion (including in the vicinitythereof) of the exciting coil 5, not only can the detection accuracy beimproved by increasing the magnetic field intensity in the vicinity ofthe detection coils 7 but also the coin identification sensor 1 can bereduced in size.

Moreover, because the detection coils 7 are differential coils capableof detecting a differential voltage and the pair of coils L1, L2constituting the differential coils are disposed along the surface ofthe coin 2, the detection accuracy can be further improved by cancelingout intrinsic errors and temperature errors of the coils L1, L2.

Moreover, because more than one detection coil 7 is provided so as tolie along the surface of the coin 2, by scanning (moving) the coinidentification sensor 1 or the coin 2 in a direction perpendicular tothe direction in which the detection coils 7 align, two-dimensionaldetection data can be obtained, and by two-dimensionally disposing aplurality of detection coils 7, two-dimensional detection data can beobtained without the coin identification sensor 1 or the coin 2 beingscanned (moved).

FIG. 6(A) is a schematic view of a coin identification sensor showing asecond embodiment, and FIG. 6(B) is a schematic view of a coinidentification sensor showing a third embodiment. As shown in thefigures, the coin identification sensor 21 of the second embodiment isprovided with an exciting coil 22 disposed so that the coil peripheralsurface is along the surface of the coin 2; and a detection coil 23disposed on the periphery thereof (including in the vicinity thereof).The coin identification sensor 31 of the third embodiment comprises anexciting coil 32 and a detection coil 33 disposed so as to sandwich thecoin 2. The thus structured coin identification sensors 21, 31 producesubstantially similar effects to those of the first embodiment.

FIG. 7 is a schematic view of a coin identification sensor showing afourth embodiment. As shown in this figure, the coin identificationsensor 41 of the fourth embodiment is provided with a core 42, anexciting coil 43 and a detection coil 44. The core 42 has a plurality ofcoin adjacent portions 42 a, and is made of a ferromagnetic material soas to form a looped magnetic circuit with the interior and the surfacespace of the coin 2 inside.

FIG. 8 is an explanatory view showing various forms of cores in the coinidentification sensor of the fourth embodiment. Cores 42 shown in thisfigure are all ferromagnetic members capable of forming a magneticcircuit, and formed using, for example, ferrite. As the shape of thecore 42, the following are adoptable: an angular or block U-shape asshown in FIG. 8(A); a U-shape as shown in FIG. 8(B); a V-shape as shownin FIG. 8(C); and a C-shape as shown in FIG. 8(D). Moreover, thedimensions of the core 42 are set in accordance with the excitationrange and, for example, when the core 42 is wide in the direction inwhich the exciting coil 43 is wound as shown in FIG. 8(E), the detectionarea can be increased by one-dimensionally disposing a multiplicity ofdetection coils 44 on the inner surface portion of the core 42.Moreover, equal effects are obtained by juxtaposing a plurality of cores42 as shown in FIG. 8(F).

The exciting coil 43 is wound around the core 42, and an AC voltage of apredetermined frequency is applied thereto. When the AC voltage isapplied to the exciting coil 43, the core 42 is AC-excited, so that anAC magnetic field along the surface of the coin 2 is generated in theinterior and the surface space of the coin 2. The position of winding ofthe exciting coil 43 around the core 42 is not limited to an upper partof the core 42 as shown in FIG. 9(A), but may be right and left legportions of the core 42 as shown in FIG. 9(B). Moreover, the excitingcoil 43 may be wound around an upper part and right and left legportions of the core 42 as shown in FIG. 9(C).

The detection coils 44 are disposed so that the coil central lines arealong the surface of the coin 2 and the coil peripheral surface arelocally opposed to the surface of the coin 2, and detect a magnetic fluxchange in the vicinity of the surface of the coin 2. That is, the coinidentification sensor 41 of the fourth embodiment is structured so as todetect a local magnetic flux change in the vicinity of the coin 2 whileforming a looped magnetic circuit by the exciting coil 43 and the core42. Consequently, while a strong magnetic field is locally generated onthe surface of the coin 2, the magnetic flux change can be accuratelydetected by the detection coils 44.

FIGS. 10(A)-10(C) and 11(A)-11(C) are explanatory views showing variousforms of detection coils in the coin identification sensor of the fourthembodiment. The detection coils 44 shown in these figures are all aircore coils. For example, in the detection coil 44 of FIG. 10(A) (equalto the one of FIG. 2), coils L1, L2 are formed by winding a lead wire towhich an insulating coating is applied, around a non-magnetic corematerial 44 a. Moreover, the one shown in FIG. 10(B) is a biaxial typein which a pair of detection coils 44 are integrated in an intersectingcondition, and these detection coils 44 are all disposed along thesurface of the coin 2.

FIG. 10(C) shows a detection coil 44 formed so that the thickness in thedirection of the coil central line is as small as possible. On theperiphery of a former (bobbin) 44 b used for the detection coil 44, twocoil winding grooves with a predetermined width (for example, 50 μm) areformed at a predetermined interval (for example, 50 μm), and thedetection coil 44 is formed by winding in layers a lead wire to which aninsulating coating is applied, along each coil winding groove. In thethus structured detection coil 44, because the thickness in thedirection of the coil central line is small and the distance between thecoils L1, L2 is short, the resolution in the direction of the coilcentral line can be significantly improved.

The detection coil 44 shown in FIGS. 11(A)-11(C) is formed as athin-film circuit pattern (spiral coil) on a base material 44 c made ofan insulating material. For example, a base material 44 c for athin-film substrate (for example, a ceramic substrate) is used, and aconductor layer (for example, a copper foil) formed on the obverse andreverse surfaces thereof is evaporated based on the circuit pattern tothereby form the thin-film coils L1, L2. According to this detectioncoil 44, because the pair of coils L1, L2, constituting a differentialcoil, are formed in layers with the extremely thin base material 44 c inbetween, the resolution in the direction of the coil central line can bedramatically improved.

In the detection coil 44 structured as described above, it is easy toone-dimensionally dispose the coils L1, L2 as shown in FIG. 11(B). Whena plurality of coils L1, L2 are one-dimensionally disposed like this, byscanning (moving) the coin identification sensor 41 or the coin 2 in adirection perpendicular to the direction in which the coils L1, L2 aredisposed, two-dimensional detection data can be obtained. Moreover,detection coils 44 in which a plurality of coils L1, L2 areone-dimensionally disposed may be juxtaposed in the direction ofscanning of the coin identification sensor 41 or the coin 2 as shown inFIG. 11(C). In this case, by disposing the coils L1, L2 formed in thefront and rear detection coils 44 so as to be shifted by half a pitchfrom each other, the gap in the direction of one-dimensional dispositionis eliminated, and the coin configuration can be detected withoutomission. A plurality of detection coils 44 may be two-dimensionallydisposed, and in this case, two-dimensional detection data is obtainedwithout the scanning of the coin identification sensor 41 or the coin 2.The detection coils 44 shown in FIGS. 10(A)-10(C) and 11(A)-11(C) areapplicable to other embodiments.

FIG. 12 is a schematic view of a coin identification sensor showing afifth embodiment. As shown in the figure, in the coin identificationsensor 51 of the fifth embodiment, an exciting coil 53 (core 52) and adetection coil 54 are disposed so as to sandwich the coin 2. The coinidentification sensor 51 structured as described above produces similareffects as those of the fourth embodiment.

Next, an exemplary coin configuration detection method according to theinvention will be described. In the coin configuration detection methodof the invention, to identify the kind and/or the authenticity of acoin, the coin configuration is magnetically detected, and while an ACmagnetic field in the direction along the surface of the coin isgenerated in the interior of the coin and/or in the surface space of thecoin, a magnetic flux change in the vicinity of the coin surface isdetected by a detection coil in which the coil central line is along thecoin surface and the coil peripheral surface is locally opposed to thecoin surface. Specifically, by using any of the above-described coinidentification sensors (1, 21, 31, 41, 51), the coin configurationdetection method of the invention can be implemented.

When the coin configuration detection method is used, while an ACmagnetic field along the coin surface is generated to thereby cause amagnetic change due to the surface configuration of the coin to emergeas a magnetic flux change mainly along the coin surface, the magneticflux change, is detected not by detection coils disposed vertically tothe coin surface but by the detection coils disposed along the coinsurface, whereby even a minute magnetic flux change whose verticalcomponent hardly changes can be detected. By this, even a fine surfaceconfiguration of the coin can be detected, so that the coinconfiguration detection accuracy can be dramatically improved. Further,because it is easy to reduce the size of the detection coils in thedirection along the coin surface, the resolution of the coinconfiguration detection can be easily improved by reducing the AX asmuch as possible.

Next, an exemplary coin identification apparatus according to theinvention will be described. The coin identification apparatus of theinvention identifies the kind and/or the authenticity of a coin, and isstructured so as to detect the coin configuration by the coinidentification sensor according to the invention (specifically, the coinidentification sensor 1, 21, 31, 41 or 51 of the above-describedembodiment) and identify the kind and/or the authenticity of the coinbased on the detected configuration.

As a concrete structure of the coin identification apparatus, forexample, the following are provided: a filter that receives detectiondata from the coin identification sensor and removes the noise thereof;a binarization processor that binarizes the detection data by use of apredetermined threshold value; a recognition area identifier thatidentifies a recognition area in the binarized data; a matchingprocessor that matches the binarized data in the recognition area withprestored coin configuration patterns; and a determination processorthat determines the kind and/or the authenticity of the coin based onthe hit rate (correlation function). These processings can be realizednot only by hardware processing using a dedicated IC or the like butalso by program processing using a microcomputer or the like.

Thus, the invention relates to a coin configuration detection method anda coin identification sensor that magnetically detects the coinconfiguration to identify the kind and/or the authenticity of the coinor to a coin identification apparatus that identifies the kind and/orthe authenticity of the coin based on the configuration detected by thecoin identification sensor. The invention is usable as the coinidentifier of vending machines and automatic ticket vending machines,and is particularly useful as a coin identification apparatus forfinancial institutions requiring high coin identification accuracy.

1. A coin configuration detection method that magnetically detects aconfiguration of a coin to identify a kind and/or authenticity of thecoin, comprising: detecting a magnetic flux change in a vicinity of asurface of the coin using a detection coil in which a coil central lineextends along the surface of the coin and a coil peripheral surface islocally opposed to the surface of the coin while an AC magnetic fieldalong the surface of the coin is generated in an interior of and/or in asurface space of the coin.
 2. A coin identification sensor thatmagnetically detects a configuration of a coin to identify a kind and/orauthenticity of the coin, comprising: an exciting portion that generatesan AC magnetic field along a surface of the coin in an interior ofand/or in a surface space of the coin; and a detection coil is disposedso that a coil central line extends along the surface of the coin and acoil peripheral surface is locally opposed to the surface of the coin,the detection coil detects a magnetic flux change in a vicinity of thesurface of the coin.
 3. The coin identification sensor according toclaim 2, wherein the exciting portion is an exciting coil disposed sothat a coil inner peripheral surface or a coil peripheral surface isalong the surface of the coin and which generates an AC magnetic fieldin the direction along the surface of the coin in the interior and/or inthe surface space of the coin, and the detection coil is disposed in orin a vicinity of an inner peripheral portion of the exciting coil ordisposed in or in a vicinity of a peripheral portion of the excitingcoil.
 4. The coin identification sensor according to claim 2, whereinthe exciting portion has a plurality of coin adjacent portions, and isprovided with a ferromagnetic core that forms a looped magnetic circuitwith the interior and the surface space of the coin inside and anexciting coil that AC-excites the core and generates an AC magneticfield in the direction along the surface in the interior of the coinand/or in the surface space of the coin.
 5. The coin identificationsensor according to claim 2, wherein the detection coil is adifferential coil capable of detecting a differential voltage, and apair of coils constitute a differential coil line along the surface ofthe coin.
 6. The coin identification sensor according to any of claim 2,wherein a plurality of detection coils are provided to line along thesurface of the coin.
 7. A coin identification apparatus that identifiesa kind and/or authenticity of a coin, wherein a configuration of thecoin is detected by the coin identification sensor according to claim 2and the kind and/or the authenticity of the coin is identified based ona detected configuration.
 8. The coin identification sensor according toclaim 3, wherein the detection coil is a differential coil capable ofdetecting a differential voltage, and a pair of coils constitute adifferential coil line along the surface of the coin.
 9. The coinidentification sensor according to claim 4, wherein the detection coilis a differential coil capable of detecting a differential voltage, anda pair of coils constitute a differential coil line along the surface ofthe coin.
 10. The coin identification sensor according to claim 3,wherein a plurality of detection coils are provided to line along thesurface of the coin.
 11. The coin identification sensor according toclaim 4, wherein a plurality of detection coils are provided to linealong the surface of the coin.
 12. The coin identification sensoraccording to claim 5, wherein a plurality of detection coils areprovided to line along the surface of the coin.
 13. The coinidentification sensor according to claim 8, wherein a plurality ofdetection coils are provided to line along the surface of the coin. 14.The coin identification sensor according to claim 9, wherein a pluralityof detection coils are provided to line along the surface of the coin.15. A coin identification apparatus that identifies a kind and/orauthenticity of a coin, wherein a configuration of the coin is detectedby the coin identification sensor according to claim 3 and the kindand/or the authenticity of the coin is identified based on a detectedconfiguration.
 16. A coin identification apparatus that identifies akind and/or authenticity of a coin, wherein a configuration of the coinis detected by the coin identification sensor according to claim 4 andthe kind and/or the authenticity of the coin is identified based on adetected configuration.
 17. A coin identification apparatus thatidentifies a kind and/or authenticity of a coin, wherein a configurationof the coin is detected by the coin identification sensor according toclaim 5 and the kind and/or the authenticity of the coin is identifiedbased on a detected configuration.
 18. A coin identification apparatusthat identifies a kind and/or authenticity of a coin, wherein aconfiguration of the coin is detected by the coin identification sensoraccording to claim 6 and the kind and/or the authenticity of the coin isidentified based on a detected configuration.
 19. A coin identificationapparatus that identifies a kind and/or authenticity of a coin, whereina configuration of the coin is detected by the coin identificationsensor according to claim 13 and the kind and/or the authenticity of thecoin is identified based on a detected configuration.
 20. A coinidentification apparatus that identifies a kind and/or authenticity of acoin, wherein a configuration of the coin is detected by the coinidentification sensor according to claim 14 and the kind and/or theauthenticity of the coin is identified based on a detectedconfiguration.